:where(.demo) a {
  color: #2b6ce1;
}
.demo {
  padding: 10px;
  details {
    margin-bottom: 1rem;
    font-size: 16px;
    summary {
      user-select: none;
      outline: 0;
      &::marker {
        font-size: 0;
      }
      .more {
        display: none;
      }
      a {
        cursor: pointer;
      }
    }
    &[open] {
      summary {
        a {
          font-size: 0;
          &::before {
            content: "收起";
            font-size: 16px;
          }
        }
        .more {
          display: block;
        }
      }
    }
  }
}
